Method for compounding solid netted black porcelain sunlight absorbing layer on ceramic solar panel

Abstract

The present invention relates to a method for compounding solid reticular black porcelain sunlight absorbing layer on ceramic solar plate, wherein, industrial waste residues and metal minerals rich in the transition elements in fourth period are used as main raw materials to be ground into slurry; the slurry is sprayed on the dry surface of a green body of a hollow ceramic solar plate through compressed air by adopting a single spray gun or a plurality of spray guns; the pressure and the flow rate of the compressed air and the proportion of the slurry are controlled, so as to lead fog drops in initial contact with the dry green body surface of the ceramic solar plate to form mud particles which have a certain strength, are relatively dry and adhere to the surface of the green body plate because of the fast water absorption of the dry green body and the surface tension of the fog drops; the subsequently sprayed fog drops first meet the mud particles which have a certain moisture absorption ability and protrude from the surface, and then the fog drops adhere to the mud particles, thus the heteropic incontinuous fog drop mud accumulation bodies which are in columnar shapes, steeple shapes, vertical wall shapes, honeycomb shapes or porous shapes, have moisture absorbed and have a certain strength are accumulated in turn; spraying is stopped before the solid accumulation bodies reach to a certain height and lose moisture absorption ability, thereby getting a solid reticular black porcelain green body layer on the surface of the hollow ceramic solar green body plate; the hollow ceramic green body plate having the solid reticular black porcelain green body layer is dried and fired under high temperature; the firing temperature and time are controlled to ensure that the solid reticular black porcelain green body layer and the green body of a hollow ceramic solar plate are simultaneously sintered into a solid reticular black porcelain layer and a porcelain hollow solar.

Description

(1) Technical field [0001] The invention relates to a method for manufacturing a solar light absorbing layer in the field of solar energy utilization, in particular to a method for compounding a sunlight absorbing layer on a ceramic solar plate, and further to a method for compounding a three-dimensional mesh black porcelain sunlight absorbing layer on a ceramic solar plate. (2) Background technology [0002] Solar energy utilization is mainly divided into photoelectric utilization and solar thermal utilization. At present, solar thermal utilization is mainly solar water heaters. Solar water heaters are divided into suffocating type and circulation type. The circulation type has higher efficiency. The heat collector mainly adopts metal tube plate heat collection Body and vacuum glass tube heat collector, metal tube plate heat collector is also called flat plate heat collector. Both have the following disadvantages: 1. The metal tube-sheet heat collector mainly adopts materia...

AI Technical Summary

Problems solved by technology

Both have the following disadvantages: 1. The metal tube-sheet heat collector mainly adopts materials such as copper and aluminum, and the structure and manufacturing process of the vacuum glass tube heat collector are relatively complicated. high

2. Both of them use black sunlight-absorbing paint applied at low temperature. Under the long-term sunlight, there will be a certain degree of aging to attenuate the sunlight absorption rate, which is one of the reasons for the efficiency and life problems.

3. It is difficult to integrate with the building due to reasons such as materials, structure and cost

300×300 mm vanadium-titanium black porcelain solar panels have an area of ​​0.09 square meters and a water capacity of 0.9kg. The water temperature can reach 100°C when the single-layer glass veneer is sun-drenched. In 1986, the vanadium-titanium black was ranked among the top solar water heaters in Shandong Province. Porcelain solar water heaters won the first prize. The water quality of the vanadium-titanium black porcelain solar water heaters was tested before and after heating, and no visible changes were found. The solar panels that have been used for more than 10 years have no signs of fading, corrosion, or aging. The black porcelain hollow solar panel method has low molding efficiency, low yield of large-sized solar panels, too many joints for small-sized panels, and cumbersome installation. It is difficult to develop into a large-scale industrial production method, and it is difficult to realize large-scale promotion and use.

[0023] 1. High price - metal tube-sheet type and vacuum glass heat collectors sell for hundreds of yuan per square meter, and the price of heat collectors alone is several times or even ten times the cost of ordinary roofs

[0024] 2. Short service life—metal and vacuum glass tube heat collectors generally use low-temperature solar coatings, and the sunlight absorption rate is easy to attenuate. Metal tube-sheet copper tubes have many welding joints, and the welding joints are easy to corrode. The coating performance decays and the welding joints corrode. The average service life of metal solar collectors is about 10 years. In addition to coating aging, vacuum glass tubes also have vacuum life, glass tube air leakage, broken and other factors. Most of the water sources in my country are hard water, with many Ca and Mg ions, which are easy to produce water. Alkali, water-alkali flocculent precipitation blocks the glass blind tube and other problems, and various reasons lead to the average life of the vacuum glass tube collector is about 10 years

In about 10 years, it usually needs to go through multiple repairs and parts replacement. The average life of about 10 years refers to a single solar water heater with a lighting area of ​​1 to 2 square meters. Repair the roof, which is unacceptable for buildings with a service life of 50 to more than 100 years

[0025] 3. The average efficiency is not high——①The low-temperature coating begins to age within a few years, and the sunlight absorption rate gradually decreases, and the average efficiency during the entire life is not high; medium, the average heat transfer distance is about 30mm

Due to structural limitations, the gap between the vacuum glass tubes is large, and the black absorbing layer only accounts for about 50% of the structural area. The sun is strong at noon, but when the sun shines directly at noon, a large amount of sunlight passes through the gap between the tubes, which affects the heat collection efficiency.

[0026] 4. Difficult to integrate with the building - the roof is composed of a structural layer, an insulation layer, and a waterproof layer, and the solar collector is composed of a structural layer, an insulation layer, a heat collection layer, and a waterproof layer (transparent layer). The so-called solar roof is bound to require Combining the two organically and sharing the functional layers of the two as much as possible can not only maintain the function of the original roof but also obtain solar energy from it for the various energy needs of the building and reduce the construction cost. As mentioned above, due to the various shortcomings of the above two heat collectors, their reliability will further decline when they are used in a large area, and it is difficult to design a reasonable solar roof structure. Even if it is designed, the following results will appear: ① The cost of the roof has increased several times to more than ten times; ②The reliability of the roof has declined, making it difficult for the Q value of this solar roof to become a large positive value

[0043] 2. The coating manufacturing process is relatively complicated or the raw materials are expensive, resulting in high coating manufacturing costs

[0044] The above problems lead to the high price and short effective service life of the coating. If the service life is 10 years, the average sunlight absorption rate is not high due to performance attenuation.

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